Mirror



Sept. 28 1926.

W, PEACocK MIRRoR Filed A r1 5, 1926 ing abSoTbed by the Silver SLII fLoe.

UNTED STA ES PATENT oFFICE.

0fy invention oonsiStS in the novel featores hereinofteI' desoribed, refeTenCe being hod to the acoonlponying dfavving vvhioh illI1S- trateS one eInbodinlent of Iny invention Se- 1eoted by Ine foI' pur oSes of illuStratioI1, and the said invention iS fully diSolosed in the fonoWing deScri tion and olaiInS.

The obieot of n1y invention is, to rodnce o perInonent Inirror oo able of refleoting inoages vith the saIne exactneSs of forIn ond oolor aS iS roduoed by tl1e beSt quality of Silvered InirroTS, but Whioh Will TeHeot the said iIIlageS vvith greatly 1oTvered in tenSity` So that vvhile the eye vvi11 receive fronl it a perfectly ooourote Tefleotion, in condeScent obiectS and otheI' obeotS of intenSe illnInination Tvill be so nlarkedly Sobdued, as to produce no iTritating effeotS oI1 the fetiIla, and no oonfuSion or obSoufo tion of other ilT1ages refleoted by the Inifror at the Some tiIne. Sooh a Inirfor, Which I hove rodnced ooII1IIleroially, iS artionlarly odapted foI' 11Se aS a rear vie for tonlobile, bnt it n1ay a So be uSed for any ofher pur oSe for whioh it Inay be fonnd advantageous of deSifab1e.

It haS been Scientioa1ly detern1ined, that l1eI e light ffon1 i11I1111inated obieotS fallS npon the Surface of 9dI1 ofdinary SilvereCl InirIor, n eXtren1ely SIno11 eroentage of the light is I'ef1 ected froIn the front Surfaoe of the glaSS Plate SuPporting on itS book the Silver ooatlng, the gTeateSt aInount of Suoh lig11t paSSing throngh the glaSS and being refieoted to the eyo of the obServer ffoIn the I'e9I faoe of the glaSS. There re,thefe fo1 e, tvo Separate fefleotions prodnced, tho one froIn the front faoe of tho glaSS, and the otheI fI'oII1 the rear faoe. The aInount of light refleoted froIn the front face of aln ordinory miTror is opproxiInately 5%, and the aTI1ount of light refleoted froII1 the 1'eLr foce iS a ProXi11tely 95% of the light tTansn1itted through the glaSS, about 5) be TheSe tvo TeHeCtionS ore not ooinCidentond their lock of ooincidenoe varieS vith the thiokneSS of the glaSS Plate, ond the voriotiolls in the angleS of inoidenoo. seriouS loCk of definition vould uSually feSult, exoe t WheI1 the obSefver vvaS difeotly i11 ffont of the Tnirror, vvere it I1ot foI' the faot that the aInonnt of light reeoted ffon1 the rear fce of the glosS is So vaStly in exoess of the aInount fefleoted ffon1 the front Srfaoe, LS to TendeTthe latteI' negligible.

In carTying Iny iflve11t1oI1 iIltoeff'eot, I hove aiTIled at the Prodnotion of a oheop Inlfror, I)Iod11oed by ooating a late of oleaI gloSS in SIlCh o IIlaJI1I1eI' aS to prevent rao t1o1y any Speoular refieotion of' diffuSe I'e eot1on of light fI'oIn the fear faoe of the glaSS, aIld to seouro oI1ly SI1ch iInages os are fefleoted froIn the ffont sl1I'faoe of the g1aS vvithout havin theIn obsoured, of Inodlfied, of eote by ony a feoioble aII1ol111t of light Ieeoted fro1 the Ie2tI faco of the glaSS, of the ooating applied thereto.

am aware of the faot that it iS Wo11 known, that a oertain kind of reeotion may be obtafned by Providing a Pieoe of oleaJI' glasS vV1th dTk booking, Suoh aS, oloth oI' a er, ond that obieotS may be said to be Toughly nliTrofod theTein. I an1 1sooWaTe of tho faot that SoIne kindS of oolored glSS, S11ch aS, Sooa11ed 9 rtistS, blaok glaSS, foI exan1Ple, vvi11 produce al veI'y sat1Sfao tofy refleotion fI'o111 its ffont SI1ffaoe, the llght penetroting into tho glaSS being ob sorbed oI' diS erSed by the igInentation thereof. ThiS glaSS, hovvever, is extTenlely ex enSive and diol11t to obtoin.

II1 n1y relin1inary eX efiIIlents, I songht to obtain the deSired reSI11t by Pinting 011 the baok of piece of glaSS With o blook ig'n1ent, bot I found thot the reSultS Wero II1oSt llI1SatiSfaotofy, oI1d. the inlageS obtained Tvere not ooII1 arable at a11 vvith thoSo obtained froII1 a Silvefed n1irro1, foi' the reaSon that I1otvvit11Standing the f ot that Such b1ok or dofk coating, as in tho revionsly knovv11 daTk baoking, vvonld ob- SoI'b sonle of the light, there vvould 11eoeS SaTily reSult in additio11 to a S1nod11 an1ount of S eoular refleotion froIT1 the reaT Surfoo a conSiderable an1ount of d if'11Se refleotioI1 oI' Soottered light froIn the reaI S11rface of froIn the adiaoent Pafts of the I)igInent ooatin hen it iS realized that tho aInount of light reHeoted fI'oII1 the fI'ont Sllffaoe of the glaSS iS only Substantiolly 5% of the light )aSSing said front suffaoe, it v7i11 bo seen thot ony IIlaiterial an1ount of lighf refieofed of SCattered fron1 the fear SIlrfooe of the glaSS, or ffon1 the ooating ap lied thereto, vi11 interfeTe vith, oonfuSe, and SPoil the definition of the image of low in tenSity fef1ected fIom the front SnffaCe of the glaSS, nd that in ordeT that t11eSe iInageS of low intenSity Inaly be eff ective, it iS neoeSSoTy to oSitively reolnde the OS sibility I1ot only of the SPeoLIlar fef1ection but alSo of tho diff11Se fef1eotion or Scatter ing of any Tnateri1 oftion of the light ffoII1 the reaI face of the glaSS, oI froln the oooting o Plied thereto, vvhiCh II1LlSt neceS` Sarily be of SIloh Charooter and be So nPplied oS to bSorb SnbStantiaHy oll of the lighf vvhioh PaSSeS beyon tho front faCe of the glaSS.

I diSCovered S the result of extendod ex PefiInentation, that by 9,I) )1} ing to the ref faoe of a pieoe of oleaI"plte glaSS, I1ni form light abSorbing Coatin in optioal oon tact thronghont SnbSfantiolly itS e11tire ex tent, ond of such chafoctef aS to obSofb S11bstantially tl1 of the light paSSing there through, that I oI1 fevent not on1yany material specular reflection, but alSo any m teTial diuSe refieotion of light froIn the rer faCe of the glaSS, OI' the oontiguous faoe of the ooating, thuS leoving the light fef1eoted ffoIn the fIoI1f f9doe of the glaSS to corry the only iIIlage refleofed thefeby, and produoe, therefofe, a TefleofioI1 aS trlle both S to forn1 nd ooloI, aS Can be ob toined froIn al Silvefed IT1iI'ror, btlt at roxiInately oIle-tWventieth of the ill11IninafioI1. This IT1irTor vvaS pToduced for the rSt tiIne by nle, and I oloiIn it broodly S Iny invention.

In the aooompanying dTawing, the figure re fesents o seotional view of a InirroI' eInbodying IIly invention, and deSigned par tiClllorly as aJ fear vievv n1irrof fof ooto- Inobiles.

II1 oarrying IIly invention into effect, I toke ooInn1ercia1 high grade poliShed lote glaSS preferably abont th of aIl inCh thiok, of the deSired size, nd preferably having itS front edges beveled by grinding in the 11SI11 Inanner. The glass plate iS thorough 1y oleaned aS by vvaShing in hot So y vvater, ofteI' v7hioh the reoI' faoe of the g1SS iS Wiped off vvith benine or other voloti1e flI1i(1, to obtain oheInioally oloan SL1Ifaoe, in order that the oooting Inoy be 11I1iforInly apP1ied in o tico1 contact at a11 pointS of the Sllrface treoted. I then oPply to the fear fooe of the glaSS plate, in optical Con tact therevvith thronghout itS enti e extent, a4- coting of Inaterial coPb1e of abSorb ing SUbStantially all light TayS folling n on it. B} OPtioal oontct I Inean thot the light abSorbing ooating is o lied in Such inti Inate relation vvith the reaI fooe of the glass thot the fer faoe of the g1SS aJnd the ffont faoe of the coating, becoIne foI' aH prcticol UrpoSeS, o Single plane of SLlrface, so faI' aS their behavior vith re S ect to light iS concerned. In order to Secllre thiS intiInofe Contoot betTveen the feor faCe of the plte and the Cooting, the glaSS iS refefobly laced in o tray in S11Ch a manner th1t only the face to be coated iS ex OSed, and iS then heoted in a gaS oven to op roxiInately 180 degTeeS fteT Which it iS reInoved ond iInInediotely Sproyed With the coating Inaterial. The late iS again heated in on oven of teInperature of a PfoxiInafely 130 degreeS to effeot the drying and reSefve the oI)tical oontact be tveen the cooting ond the glaSS. ThiS fen derS the Inirrof erInanent and preventS the oooting, or any porfion of it, from getting oLlt of oPtio1 contact vith the rear foCe of the g1SS under ofdinary atn1OSPheric oon dition. fo roteot the coting, and fur ther prevent it fron1 being adverSely attacked by extraordinoTy atInoS herio oon ditionS, it iS referably fovided ,vith Profeoting ooating of Sin1i1r n1ateriol, aS hereinofter deScribed.

The coating vvhich I pTefe1' to eInploy conSists of li(1L1id yrOXy1in locquef ooIn bined With blok pigment, aS lompblack,

for example. I have found S a mttof of ex erinlent, that the addition of a sInLl1 quontity of a Colored pigInent by vhioh I n1ean one of the fiInafy colorS of the S ectrI1In, (of the hueS thereof) nd eXC111 ing vvhite and b1ok p earS to iIT1 rt a ve1 vety ohracter to t11e Coating and So1T1evhIt increaSe itS light abSorbing qllalitieS, vith Out hovever, iIT1 )Irfing Iny of thiS coloI' in any Woy to the reHected ilnogeq Which of coIIrSe, iS feflected only froIn the ffont late of the gloSS, nd Whioh iS not in ny vvay Inodified by the oolor of the coating, the function of vhioh iS Tnerely to obSorb Snb Stontia11y evefy aTtiole of light aSSing be yond the front st1rfCe of the glaSS, nd )revenfing not only S eoulor ref1eotion. but olso CliffI1Se refleotion or Sottering of light froIn the reaf foce of the glaSS, of froIn the contiguonS foce of the cooting. The ign1enf vvhich I refer to nSe iS blue )igII1ent, and I hve found the beSt fe SLIltS obtained by the L1Se vith l1n blook or other black, of oobalt blne, in the roortion of SubStantially ve partS of the black pigment to one art of the blne pig- Inent, or oobalt.

1fter the coating iS entirely dried ond before the heat hS left the 1aSS, 3J Protecting ooating is ap lied to the HrSt coat ing and dried in the SaIne vvoy. ThiS pfoteoting coating Inay be of ony deSired chor nof shovo the allSt. The pfoteoting ooot ing obove deSCfibed, vvill pfoteot the light obSofbing cooting ffon1 tho effeofS of of- InoS hefio conditionS, ond it vil1 be noted thot I pfefefobly employ the Some ty o of nlotefiol fof both the lighf obSofbing Coot ing ond the fofeoting Cooting, to vif, yfoxylin looquef contoining the ign1ent n]otefioL It follovS, thefefofe, thot the tv0 cootingS ex ond ond conffoot focfioolly equolly Undef Chon eS of teInPerotufe, So thot thefe is no tendenoy fof the pfofecting oooting, undef the effectS of teInPofotufo chonges, (1iStllfbing the o1)ticol oon toct betWeen the light obSofbing oooting ond fhe feof foce of the gloSS, I hovo olso found, by footiool ex ofienoe, thot fhe pyfoxylin locqUefS ofe Sllfficiently eloStio to toke cofe of o-Ily ineqllolity betveen theif ex onSion ond oontfoction ondef teInpefo tufe chongeS, ond thot of the gfosS lote, ond in Pfoctice it hoS been fonnd fhot thefe iS no tendency, vhotevef, of the light obsofbing cooting, of ony oftion of it, loS- ing itS oPtiool oontoot Tvith the glasS, o1 though expoSed to high of lovv teIn efo tllfeS, of exffenleS of dfyneSS ond huInidity.

In the ocooIn onying dfoWing, 1, fepfe Sents the glosS lote, hoving the ffont fe fiecting foce, 2, ond the feof fooe, 3, fe feSents the light obSofbing oooting o I)lied to the foce, 3, in unifofIn o ticol con toot thefevvith, ond conStfucted to obSofb SubStontiolly oll light osSing beyond the ffont foce, 2, ond to pfevent eithef S eclllof fefiection of CliffflSe feHection of light ffoln the reof foce, 3, of the oontigtIouS foCe of the oooting, o fepfeSentS the extefiof pfoteoting oooting op lied ovef the book of the light obS01bing oooting. v

In the dfovving fof IIf )oSeS of illl1S tfotion, I hove Shown o line 7o, o, fe fe Senting the foyS of Hght ffom on object os on electfic hght indicoted of Zc, ond eXtending thefeffoIn to the ffont SI1ffoce, 2, of the gloSS, ond thfough the gloSS of the Iniffof to tho feof SI1ffoce, 3, ond into the light obSofbing oooting, oS indicoted ot o. I hove olSo indicoted by the light line, 7o, Z), tho fefiection ffon1 the ffont foce, 2, of the miffof fodnoed by the light foy, 7o, o, ond being subStontiolly 5% only in intensity, While giving o peffeot ond ooourote feflection of the obieot, oS indicoted in light liI1eS ot b11t in I)rO poftionolly lOvef illun1inotion, thot iS to soy, oS 5% to 7. This iS, of c011fSe, Inefely o diogfoInnlotio fe feSentotion of f-he Inottef fof the pI11 )oSe of illllStfofioI1.

It vvi11 be undefStood, thot the Iniffof Inoy be Suppoffed in ony SLlitoble poft of oI1 oIItoInobile of vehiole, of ploced vvhere its llSe Inoy be odvontogeouS, by ony de Sifed fofIn of n1ounting of Sop oft.

The n1iffof en1bod ing Iny invention fvill be found to feHeot o11 obieotS With the soIne Clofity ond peffection of foflT1 ond Colof, oS the beSt gfodo Silvefed n1iffof vithout the SlighteSt diStoftion, ConfuSion of lock of ClefinitioI1, bot of o gfeotly feduced degfee of illun1inotion, o fOXiInotely onetvveI1- tieth of the omoonf of 1i ht feflecfed ffoIn o Silvefed II1iffof, but vith I1o loSS of eithef (Ietoil of occurooy. There Will be neither feflection of diffuSion of light to ony o Pfeoioble e} fent ovhofevef ffon1 the foof foce of the gloSS of the configIlouS ooot ing, to n1of of inteffefe With the effeof iInoge reHected fron1 the ffont fooe of the gloSS. The odvontogeS of thiS Iniffof oS o feof view n1iffof, Tvill be ot once opPofent. II1 the fifSt Ploce, dufing the doy, fegofdleSS of Whethef thefe iS high of low illIlIninotion, o peffeot feection iS pfovided ot oll tinleS eqnol to thot of ony Silvefed Inif- L fof, TVhile the foot thof only o f0ifnotely one tventiefh of the light iS feHected to fhe eye of the obServef, feSLlltS in o fe Ino1 loble felief to the eye, ond vvflich odds gfeotly to CoInfort in dfiving. In dfiving ot nighf vvith ony Iniffof, thefe is little fefleoted, exce t inoondesoeIlt of vefy highly illoIninoted objeots, poftionlofly heod lightS of vehioleS op fooching ffoIn the feof; vhich in tho oose of on ofdinofy Inif1 of pfoduce on intenSe glofe, blinding the ob- Servef by effecfing controotion of the ifis, So thot I1othiI1g iS oleofly SeeI1 in the Iniffof, nof on the food oheod.

By the llSe of nly iIn foved Iniffof, the 100 Hght ffon1 the heod lightS of vehioleS in fhe feof, of othef objeofS of intenSe illuIninotion follin u on the n fo 0xi- Inofely nineteentoventiofhS obSofbed, o foxiInotely ofle-tfventieth only being fe 1o fiecfed ffon1 fhe ffont foce of the Iniffof, vifh the feSult thot tho inooge even of in condeSoent objecfS doeS not irritote the 'eti Ilo, o effect ony Ino oI 1o coSlng o the ifiS, on e obSefvef iS, thefefofo, given o effeotly oCotlfote fofleotion of fvhot iS behind hiIn, in So fof oS it iS ill[1IniI1oted ot oll, o hile hiS eyeS feInoin in o Condi tion to See obieofS fofvofd of hiS oof, oS cleofly oS if hood lightS of othef incondeS- cent of highly illlllT1inofed obiecfS T,efe not being feeoted in the miffof of oH. My in1 foved Iniffof contfibnteS gfootly of night to Sofety in (11 iving onton1otive vehicleS, ond in the doy tiIne contributeS gfootly fo the coInfoft ond feloxotion of the dfivef by fefieving hiS eyoS of 111I1eCeSSory Stfoin, vhile pfeSenting oS oleof ond oCollfofe refleote(1 iInogeS, oS oon be obtoineLl floln the beSt qIlolity of Silvefed IniffofS.

In coffying ollt Iny invention I om oble to fovide o Iniffof hoving the ohofoctefiSticS pfovionSly dosofibed, vhiCh oon be coInnlefciolly rodnced ot o lovv Price, en obling it to be feodily mode up ond So1(1 130 ol1t the entiro rear Surface of the g1SS Plate, Said coating being co able of abSorbing Sub- Stantially oll of the light poSSing in rear of the front face of the glaSS plote ond prevent ing the SpeCnlaf feflection oI' the diuSe re, fleCtion of light f1'OIn the fear face of the gloSS late or froIn the contiguous face of Soid ooating, vvhereby tI'lle, acouTote, and Well dened images Will be at al1 tiIneS fe flected froIn the Inirror at gret1y reduCed 10 illnInination.

In teStin1ony Whereof I ax Iny Signature. 

